Load and local muscular isometric endurance with occluded blood supply

1964 ◽  
Vol 19 (6) ◽  
pp. 1135-1138 ◽  
Author(s):  
K. B. Start
Keyword(s):  
Blood Supply ◽  
Vascular Occlusion ◽  
Muscle Group ◽  
Maximum Strength ◽  
High Loading ◽  
Upper Arm ◽  
Isometric Endurance ◽  
Pressure Cuff

The isometric endurance of the palmar flexors was measured in 11 subjects who had the blood supply to the forearm occluded by means of a pressure cuff on the upper arm. The endurance load was determined as a percentage of the maximum strength of each muscle group and, in this study, varied from 35 to 85%. Load was graphed against endurance and equations were established for the relation which, under the conditions of high loading in the experiment, appeared to be linear. contraction metabolism; strength as a predictor of endurance; contraction producing intramuscular vascular occlusion Submitted on December 30, 1963

Local muscle endurance with open and occluded intramuscular circulation

1963 ◽  
Vol 18 (4) ◽  
pp. 804-807 ◽  
Author(s):  
K. B. Start ◽  
Rosemary Holmes
Keyword(s):  
Blood Supply ◽  
Muscle Group ◽  
The Other ◽  
Maximum Strength ◽  
Muscle Endurance ◽  
Elbow Flexors ◽  
Active Muscle ◽  
Isometric Endurance ◽  
Pressure Cuff ◽  
Female Subjects

The local isometric endurance of the elbow flexors of four groups of five female subjects was tested. Two groups had the circulation to the contracting muscles occluded by a pressure cuff and the others had normal circulations. One group in each of the open and occluded conditions worked with a load equivalent to one-third of maximum strength and the other group worked against a resistance of two-thirds of maximum strength. The endurances of the two groups working with two-thirds of maximum strength as load were not significantly different despite the occlusion of the blood supply in one of the groups. The endurance of the group with open circulation and one-third of maximum strength as load was significantly greater than that of the group with the same load but with occluded blood supply. Only at this lower level of loading did the artificial occlusion of the blood supply to the active muscle group appear to reduce its endurance. Submitted on October 19, 1962

scholarly journals New insights into the biomechanics of Legg-Calvé-Perthes’ disease

2018 ◽  
Vol 7 (2) ◽  
pp. 148-156 ◽  
Author(s):  
M. Pinheiro ◽  
C. A. Dobson ◽  
D. Perry ◽  
M. J. Fagan
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Blood Supply ◽  
Vascular Occlusion ◽  
Perthes Disease ◽  
Element Analysis ◽  
Vascular Obstruction ◽  
Delayed Ossification ◽  
Skeletal Immaturity

Objectives Legg–Calvé–Perthes’ disease (LCP) is an idiopathic osteonecrosis of the femoral head that is most common in children between four and eight years old. The factors that lead to the onset of LCP are still unclear; however, it is believed that interruption of the blood supply to the developing epiphysis is an important factor in the development of the condition. Methods Finite element analysis modelling of the blood supply to the juvenile epiphysis was investigated to understand under which circumstances the blood vessels supplying the femoral epiphysis could become obstructed. The identification of these conditions is likely to be important in understanding the biomechanics of LCP. Results The results support the hypothesis that vascular obstruction to the epiphysis may arise when there is delayed ossification and when articular cartilage has reduced stiffness under compression. Conclusion The findings support the theory of vascular occlusion as being important in the pathophysiology of Perthes disease. Cite this article: M. Pinheiro, C. A. Dobson, D. Perry, M. J. Fagan. New insights into the biomechanics of Legg-Calvé-Perthes’ disease: The Role of Epiphyseal Skeletal Immaturity in Vascular Obstruction. Bone Joint Res 2018;7:148–156. DOI: 10.1302/2046-3758.72.BJR-2017-0191.R1.

Blood Pressure Cuff Confusion

PEDIATRICS ◽  
1988 ◽  
Vol 81 (2) ◽  
pp. 328-329
Author(s):  
JENNIFER LOGGIE
Keyword(s):  
Blood Pressure ◽  
Blood Pressure Control ◽  
Task Force ◽  
Pressure Control ◽  
Blood Pressure Cuff ◽  
Upper Arm ◽  
Pressure Cuff ◽  
Published Report ◽  
Transcription Error ◽  
Cuff Size

To the Editor.— Since the report of the Second Task Force on Blood Pressure Control in Children (Pediatrics 1987;79:1-25) was published, several individuals have asked me (1) why we changed the recommendation for cuff size from one that covers two thirds to one that covers three quarters of the upper arm and (2) what data formed the basis for this change in recommendations? When I reread the published report to verify cuff size recommendations, it appeared to me that somewhere along the line a transcription error had taken place.

Clinical Comparison of Automatic, Noninvasive Measurements of Blood Pressure in the Forearm and Upper Arm

2005 ◽  
Vol 14 (3) ◽  
pp. 232-241 ◽  
Author(s):  
Kathleen Schell ◽  
Elisabeth Bradley ◽  
Linda Bucher ◽  
Maureen Seckel ◽  
Denise Lyons ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Pressure ◽  
Vital Signs ◽  
Stable Condition ◽  
Correlation Coefficients ◽  
Upper Arm ◽  
Mean Values ◽  
Noninvasive Measurements ◽  
Measure Blood Pressure ◽  
Pressure Cuff

• Background When the upper arm (area from shoulder to elbow) is inaccessible and/or a standard-sized blood pressure cuff does not fit, some healthcare workers use the forearm to measure blood pressure. • Objective To compare automatic noninvasive measurements of blood pressure in the upper arm and forearm. • Methods A descriptive, correlational comparison study was conducted in the emergency department of a 1071-bed teaching hospital. Subjects were 204 English-speaking patients 6 to 91 years old in medically stable condition who had entered the department on foot or by wheelchair and who had no exclusions to using their left upper extremity. A Welch Allyn Vital Signs 420 series monitor was used to measure blood pressure in the left upper arm and forearm with the subject seated and the upper arm or forearm at heart level. • Results Pearson r correlation coefficients between measurements in the upper arm and forearm were 0.88 for systolic blood pressure and 0.76 for diastolic blood pressure (P < .001 for both). Mean systolic pressures, but not mean diastolic pressures, in the upper arm and forearm differed significantly (t = 2.07, P = .04). A Bland-Altman analysis indicated that the distances between the mean values and the limits of agreement for the 2 sites ranged from 15 mm Hg (mean arterial pressure) to 18.4 mm Hg (systolic pressure). • Conclusions Despite strict attention to correct cuff size and placement of the upper arm or forearm at heart level, measurements of blood pressure obtained noninvasively in the arm and forearm of seated patients in stable condition are not interchangeable.

Evidence for a fatigue-induced reflex inhibition of motoneuron firing rates

1987 ◽  
Vol 58 (1) ◽  
pp. 125-137 ◽  
Author(s):  
J. J. Woods ◽  
F. Furbush ◽  
B. Bigland-Ritchie
Keyword(s):  
Blood Supply ◽  
Muscle Activation ◽  
Biceps Brachii ◽  
Voluntary Contraction ◽  
Adductor Pollicis ◽  
Full Recovery ◽  
Firing Rates ◽  
Peripheral Muscle ◽  
Pressure Cuff ◽  
Before And After

1. In previous studies on the adductor pollicis and biceps brachii muscles we suggested that motoneuron firing rates are inhibited by a reflex from the muscle during fatigue, since: the firing rates decline during a sustained maximal voluntary contraction (MVC); recovery of MVC firing rates is prevented if the fatigued state of the muscle is preserved for 3 min by local occlusion of its blood supply; and full recovery occurs during this time once the blood supply to the peripheral muscle is restored. These findings were confirmed in the present study for quadriceps contractions. 2. These results do not necessarily imply an inhibitory reflex. The lower firing rates recorded from the muscle fibers during an MVC following 3 min of postfatigue ischemia may have been caused by either reduced subject effort (decreased muscle activation by the CNS) or impaired peripheral impulse transmission under these conditions. The present experiments, carried out on the quadriceps and adductor pollicis muscles, were designed to test this alternative explanation. 3. For both muscles, MVC contractions were sustained for 40 s with a blood pressure cuff inflated to 200 mmHg. This was followed by 3 min ischemic rest and a second 20-s MVC before cuff release. Three minutes after the blood supply to the muscle was restored a third 20-s MVC was made. Single shocks were delivered to the muscle throughout to record twitches from the relaxed muscle (Tr) before and after each MVC, and any twitches super-imposed on the voluntary contractions (Ts). The degree to which the muscle could be activated by voluntary effort was assessed from the ratio [1 - Ts/Tr]. For adductor pollicis, changes in the amplitude of the evoked M-waves were also measured. 4. Spike frequencies were only recorded during quadriceps experiments. These declined by 30% during the initial 40-s MVC. No recovery was seen in the second MVC following 3 min ischemic rest, but full recovery occurred within 3 min of cuff release. 5. Failure to retain full muscle activation was frequently seen in all three MVCs. However, for many well-motivated subjects twitch occlusion showed no reduction in the degree to which either the adductor pollicis or quadriceps muscles could be activated voluntarily during the MVC executed after 3 min of ischemic rest compared with that performed 3 min after the blood supply had been restored.(ABSTRACT TRUNCATED AT 400 WORDS)

The FACT : Use of a novel intermittent pneumatic compression device to promote pre-surgery arm vein dilation in patients with chronic renal failure

2021 ◽  
pp. 112972982110573
Author(s):  
Mary Hammes ◽  
Sanjay Desai ◽  
John F Lucas ◽  
Nivedita Mitta ◽  
Abhishek Pulla ◽  
...  
Keyword(s):  
Intermittent Pneumatic Compression ◽  
Cephalic Vein ◽  
Upper Arm ◽  
Flow Capacity ◽  
Pressure Cuff ◽  
Arm Vein ◽  
Secondary Endpoints ◽  
Mean Differences ◽  
Stage Renal Disease ◽  
End Stage

Background: Arteriovenous fistula (AVF) creation and maturation for hemodialysis is globally a topic of importance given the poor results and high costs associated with renal care. Successful AVF (surgical or endovascular) creation requires appropriate superficial veins and quality arteries. Many procedures fail due to initial small veins with limited blood flow capacity and distensibility. Intermittent pneumatic compression has previously shown success in trials to increase superficial veins in patients with end stage renal disease post AVF. The objective of this study is to investigate the role of an intermittent pneumatic device, the Fist Assist®, to dilate cephalic arm veins in patients with advanced chronic kidney disease (CKD) prior to AVF placement. Methods: Three centers enrolled subjects from June 2019 through July 2021. Baseline Doppler measurements of the cephalic vein in standard locations the forearm and upper arm with and without a blood pressure cuff were recorded. Patients were instructed and used Fist Assist® on their non-dominant arm for up to 4 h daily for 90 days. At approximately 3 months, Doppler measurements were repeated. The primary endpoint was cephalic vein enlargement with secondary endpoints based on percentage of veins approaching 2.5 mm in the forearm and 3.5 mm in the upper arm. Results: Thirty-seven subjects with CKD (mean eGFR 13.8 mL/min) were enrolled and completed the trial. Paired-difference t-tests (one tail) for aggregate data showed significant venous dilation of the cephalic vein in both the forearm and upper arm after use with the Fist Assist® ( p < 0.05). Mean differences in the forearm veins were approximately 0.6 and 1.1 mm in the upper arm cephalic vein after Fist Assist® application. There were no major complications reported by any subject during the trial. Conclusions: Fist Assist® use in patients with CKD is effective to enhance vein dilation. Forearm and upper arm cephalic veins increased on average 0.6 and 1.1 mm respectively after Fist Assist® application. This is the first trial to evaluate the effect of intermittent, focal pneumatic compression on pre-surgery vein diameter in patients with advanced CKD before AVF creation.

scholarly journals Considerations on the corrosion of orthodontic metallic brackets

2015 ◽  
Vol 61 (1) ◽  
pp. 25-28
Author(s):  
Ionuţ-Cornel Ionescu ◽  
◽  
Ecaterina Ionescu ◽  
Keyword(s):  
Corrosion Resistance ◽  
Blood Supply ◽  
Dental Care ◽  
Artificial Saliva ◽  
Maximum Strength ◽  
Medical Treatments ◽  
Ph Values

The effectiveness of medical treatments depends on thorough knowledge of materials and techniques used. This is especially important in dentistry due to rich blood supply and the importance of the area in the patient’s psyche. Corrosion resistance is an important feature of all metal appliances used in dental care. We tested the corrosion resistance of metal brackets using a galvanostat and three artificial saliva solutions, formulated to have different pH levels. The results show that the maximum strength is obtained at pH values close to neutral.

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